The Environmental Protection Agency (EPA) is approving a revision to the Indiana particulate matter State Implementation Plan (SIP) that Indiana submitted to EPA on September 16, 2021, for the Vertellus Agriculture and Nutrition Specialties, LLC (Vertellus) facility located in Indianapolis, Marion County. Indiana requested revisions to incorporate site-specific updates to the particulate matter emission limits for Vertellus. The updates reflect revised emission rates for particulate matter resulting from process changes related to control strategies for other pollutants. The SIP submission request also removes requirements that applied to units no longer in operation and updates language to reflect a switch from petroleum oil to natural gas for certain units. These changes represent a decrease in overall particulate matter emissions.